<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>请求超时</title>
</head>
<body>
    
    <script>

        const url = 'https://www.imooc.com/api/http/jsonp?callback=handleResponse';

        const xhr = new XMLHttpRequest();

        xhr.onreadystatechange = ()=>{
            if(xhr.readyState !== 4) return;
            if((xhr.status >= 200 || xhr.status < 300) || xhr.status === 304){
                console.log(xhr.response);
            }
        }

        xhr.open('GET',url,true);

        // 响应超时
        xhr.timeout = 10000;

        xhr.send(null);
    </script>
</body>
</html>